Hemoabdomen in dogs and cats: recognizing internal bleeding before it's too late.
Sudden collapse. Pale gums. Weakness that seems to come out of nowhere. These are the classic signs of hemoabdomen — bleeding into the abdominal cavity — and they represent one of the most time-critical emergencies in veterinary medicine.
If your dog or cat suddenly collapses, seems profoundly weak, or has very pale gums, come in immediately or go to the nearest 24/7 emergency veterinary hospital. Hemoabdomen can be fatal within hours. Dogwood is open 24/7 in Marietta — call (404) 609-1234.
Hemoabdomen simply means blood in the abdominal cavity. It happens when a blood vessel or an organ inside the abdomen ruptures and bleeds into the space around the intestines and abdominal organs. Because the abdomen can hold a large volume of blood before it becomes visibly distended, dogs and cats can lose a significant portion of their circulating blood volume before the outside signs become dramatic.
How hemoabdomen usually presents.
The most common presentation is a dog or cat — often a middle-aged to older large-breed dog — who suddenly can’t stand up or seems profoundly weak. Owners often describe it as “they were fine this morning.” On exam, gums look pale or muddy, the heart rate is elevated, the pulse is weak, and the abdomen may feel distended.
Some patients bleed slowly and present over 12–24 hours with progressive lethargy and weakness. Others bleed quickly and can collapse within minutes. Both patterns are true emergencies.
- Sudden collapse or profound weakness
- Pale or muddy gum color
- Rapid, weak pulse
- Distended (bloated-feeling) abdomen
- Cold extremities
- Sometimes vomiting or restlessness beforehand
- Occasionally a soft, wobbly gait or trouble getting up
What causes hemoabdomen in pets.
The most common cause of atraumatic (non-trauma) hemoabdomen in dogs is a bleeding splenic mass — most often hemangiosarcoma, sometimes a benign hematoma. Other causes include bleeding liver tumors, adrenal tumors, rupture of an abnormal blood vessel, and coagulopathies (bleeding disorders) from rodenticide toxicity or immune-mediated disease.
Trauma — hit by car, fall from height, dog bite — is another important cause. In these cases, hemoabdomen may occur alongside pulmonary contusions, chest injuries, or urinary tract injuries. See our related blog on splenic mass and internal bleeding in dogs.
Emergency evaluation and treatment.
Time to diagnosis and treatment matters. On arrival, our emergency team evaluates the patient with a focused abdominal ultrasound (AFAST scan), rapid bloodwork including a PCV/hematocrit and clotting profile, and vital signs. If free abdominal fluid is present and it’s blood, we know we’re dealing with hemoabdomen.
Treatment includes IV fluid resuscitation, blood product transfusion if the patient is significantly anemic, and abdominal exploratory surgery if the source of bleeding is a mass. In coagulopathy cases, treatment focuses on plasma products and reversing the underlying cause. Dogwood’s 24/7 blood bank, on-site ultrasound, and surgical suites make this integrated care possible under one roof.
The two-thirds rule. For splenic masses that rupture, roughly two-thirds are malignant hemangiosarcoma and roughly two-thirds of hemangiosarcoma patients survive surgery, but long-term prognosis with hemangiosarcoma is guarded. However, one-third are benign, and those patients often do very well after splenectomy. The only reliable way to know which is which is surgery plus biopsy.
Frequently asked questions
Can hemoabdomen resolve on its own?
Very rarely. In a small number of cases with slow bleeding from a mass, the bleeding may temporarily stop, but the underlying cause remains — and rebleeding is common. Anything more than very mild internal bleeding needs emergency evaluation.
Is surgery always required?
For hemoabdomen caused by a bleeding mass, surgery is usually necessary both to stop the bleeding and to determine what the mass is. Coagulopathy-related hemoabdomen (from rodenticide, for example) is often treated medically without surgery.
What is the prognosis after splenectomy for hemoabdomen?
It depends heavily on what the mass turns out to be. Benign masses (hematomas) often mean a full recovery. Malignant masses like hemangiosarcoma have a guarded long-term prognosis, but many families still choose surgery to relieve the immediate crisis and gain time. Our oncology team can discuss follow-up options if hemangiosarcoma is confirmed.
What is an AFAST scan?
AFAST stands for Abdominal Focused Assessment with Sonography for Trauma. It’s a quick bedside ultrasound that checks for free fluid in the abdomen. It takes only a few minutes and is one of the fastest ways to confirm hemoabdomen.
Should I do CPR at home if my pet collapses?
Call the hospital first and come in immediately. If your pet is not breathing, gentle chest compressions can be attempted, but the priority is getting to emergency care as fast as possible.